The extent of treatment varies with the stage of disease. Patients with advanced stage disease are usually given 6 to 8 cycles of chemotherapy, whereas patients with early-stage disease receive 3 to 6 cycles. Each cycle of therapy is typically 21 days (3 weeks) in length, although treatment is usually administered on Day 1, or at the most once per week each cycle.
Risk of Recurrence
The initial response to treatment for ovarian cancer is generally quite good, with approximately 70% to 80% of women having a complete clinical response that can be evidenced by a return of the CA-125 level to within a normal range, a negative CT scan, and a negative physical exam. However, if a surgical exploration were performed at this time, nearly half of these women would still have microscopic evidence of disease.
This means that a cancer recurrence is expected at some point for women who have advanced cancer at diagnosis irrespective of their good initial response to treatment. In an ongoing effort to improve disease response and provide longer-lasting disease-free intervals, there are clinical trials for first-line treatment of ovarian cancer that include combinations of a variety of drugs in different treatment regimens.
Although there is no proven scientific benefit of extending treatment beyond 6 to 8 courses of chemotherapy, some physicians are currently working to answer the question of whether there is some benefit to be gained. Some treatments under consideration include chemotherapy with several new drugs, intraperitoneal therapy, hormonal therapy, biologic therapy, and immunotherapy.
To date, there is no indication that additional courses of therapy offer more protection from recurrent disease. However, it is important that women with ovarian cancer consider participating in clinical trials that are designed to answer this question.
In general, radiation therapy is not used for first-line therapy in ovarian cancer in the United States. Radiation therapy can be used after primary debulking therapy for ovarian cancer with a technique known as whole abdominal radiotherapy.
Because certain tissues cannot tolerate large doses of radiation, whole abdominal radiotherapy must be given cautiously. Early side effects of this treatment include fatigue, nausea, vomiting, anorexia, diarrhea with some abdominal cramping, and lowering of white and red blood cells and platelets. Late effects are lung scarring (fibrosis) because the upper abdominal field can include the base of the lungs; liver toxicity, which shows as elevations in some liver function blood tests; and effects on the gastrointestinal tract that may result in chronic diarrhea, decreased absorption of nutrients, and, in some cases, blockage of the intestine that may require surgery.
Intraperitoneal (intra-abdominal) therapy is a treatment that administers medication into the abdominal cavity through a tube or catheter that has been inserted through the abdominal wall. This tube can be a permanent one such as a Port-A-Cath® (very similar to those used in the upper chest wall for intravenous therapy); other tubes, such as dialysis catheters, which can remain indefinitely; or temporary ones that can be placed and removed in a single visit.
These catheters can be used to infuse fluid that may contain chemotherapy such as cisplatin or biologic therapy such as interferon. New gene therapy studies have used this method for delivery of some novel agents.
The idea of intraperitoneal therapy is based on the concept that the ovarian tumor is typically confined to the abdominal cavity. By putting the therapy directly into the abdominal cavity, the treatment can wash over the surfaces of the cavity and the organs within, bathing the tumor directly with a therapeutic agent. A variety of treatments have been tried with some benefit in certain groups of patients.
Intraperitoneal therapy success is limited by the amount of disease within the abdomen, meaning that penetration of the treatment may be limited by the size of the tumor or because of scar tissue. This therapy involves placing fluid containing the treatment into the abdomen, and then having the woman rotate her body in several different positions to ensure adequate treatment of all surfaces. This fluid is absorbed over 24 to 48 hours. Some of the side effects of the treatment are related to the volume of fluid infused and may include: swelling, indigestion, nausea, vomiting, and changes in bowel function.
The biologic therapies and gene therapies can cause fevers. There are risks including an infection called peritonitis (inflammation of the peritoneal cavity) or problems related to the catheter, such as infection or damage to organs. Intraperitoneal therapy can be useful in controlling ascites (fluid in the abdominal cavity) in recurrent cancer. Overall, the use of intraperitoneal therapy depends on your particular oncologist or it is performed as a part of a clinical trial.
A clinical trial is a research study that evaluates new treatment options. It may also be called a clinical study or research protocol. The purpose of a clinical trial is to determine whether a newer treatment option is safe and effective. It is likely that the current therapy you are receiving for ovarian cancer was proven effective based on past clinical trials.
During your treatment, your doctor may suggest that you consider being part of a clinical trial. This does not mean that you are being asked to be a “guinea pig” or that here are no other treatment options. A clinical trial is appropriate when there is some reason to believe that the newer treatment being studied may be a good option for some patients.
According to the 2002 National Comprehensive Cancer Network (NCCN) Guidelines for Ovarian Cancer, women who have a complete response to first-line treatment, regardless of the stage of ovarian cancer, are generally monitored by their gynecologist/oncologist according to the following schedule of visits and tests:
Visit the oncologist every 2 to 4 months for 2 years, then every 6 months for 3 years.
Conduct a complete blood count (CBC
) every 12 months or as indicated Test CA-125 level at every appointment if initially elevated.
Obtain a chemistry profile if indicated Have a physical exam, including pelvic exam.
Obtain an abdominopelvic CT scan if clinically indicated Get a chest x-ray exam as indicated.
Overall, approximately 70% to 80% of women diagnosed with stage III or IV ovarian cancer will have a complete response to initial treatment that can be measured by a normal CA-125 level, a negative physical exam, and negative abdominopelvic CT scan. Nearly all oncologists agree that carboplatin plus paclitaxel is the most effective combination in the treatment of ovarian cancer.
However, if a woman’s ovarian cancer fails to respond to a platinum drug or recurs within the 3 to 6 months following first-line therapy, she has a much lower chance of responding to any other chemotherapy agent. Despite the high level of response to first-line therapy, a majority of women will have recurrent disease requiring additional treatment. In this situation, the medical management of ovarian cancer may shift to thinking in terms of stopping or slowing the spread of the disease by maximizing the number of chemotherapy agents a woman can be exposed to while minimizing and timing the onset of treatment-related side effects.
Recurrent ovarian cancer is not an automatic death sentence. It is critical for you to discuss planning for a sequence of future treatments with your oncologist.
Social networking and online support groups are important tools. Reaching out to others who have or have had similar experiences can provide you with valuable insights. Check out Cancer Support Community's The Living Room
for more information on clinically faciliated support online.